β-连环蛋白保护肝缺血再灌注损伤的机制研究

The protective role of β-catenin in liver ischemia-reperfusion injury

目的应用特异性基因敲除小鼠模型研究β-连环蛋白(β-catenin)对小鼠肝缺血再灌注损伤的保护机制。方法建立β-catenin基因敲除小鼠(实验组,6只)和野生型小鼠(对照组,6只)肝缺血再灌注模型,采用原位末端转移酶标记技术(TUNEL)法检测两组小鼠肝组织细胞凋亡;应用实时定量聚合酶链反应(PCR)技术测定两组小鼠再灌注后0、6 h时的肝细胞白细胞介素-6(IL-6)mRNA及肿瘤坏死因子-α(TNF-α)mRNA表达水平。结果肝脏缺血再灌注0 h时,实验组肝细胞凋亡数、TNF-αmRNA、IL-6 mRNA与对照组间的差异均无统计学意义(P值均>0.05)。缺血再灌注6 h时,实验组凋亡细胞数为(56±15)个/高倍视野,显著多于对照组的(27±8)个/高倍视野(P<0.05);实验组TNF-αmRNA、IL-6 mRNA分别为2.5±0.3、7.8±2.6,均显著高于对照组的1.1±0.1、4.8±1.3,差异均有统计学意义(P值均<0.05)。结论β-catenin可通过抗凋亡和抗炎作用对肝脏缺血再灌注引起的细胞损伤起保护作用。

Objective To study the protective mechanism of β-catenin in liver ischemia-reperfusion injury in conditional knockout （KO） mice. Methods Liver ischemia-reperfusion injury models were created in β-catenin conditional knockout mice （experimental group, n=6） and wild type mice （control group, n = 6）. Cell apoptosis were detected by TdT-mediated dUTP nick end labeling （TUNEL） staining and mRNA levels of tumor necrosis factor-α （TNF-α） and interleukin-6 （IL-6） were measured by real-time polymerase chain reaction （PCR） at 0 h and 6 h time points after ischemia-reperfusion. Results At 0 h time point, cell apoptosis and inflammation factors （TNF-α and IL-6） between the two groups had no significant difference （all P〈0.05）. At 6 h of reperfusion, there were much more apoptotic cells in experimental group （[56± 15] vs. [27±8] per high-power field） compared with control group mRNA levels of TNF-α （[2.5± 0.3] vs. [1. 1± 0. 1]） and IL-6 （[7.8±2.6] vs. [4.8 ± 1.31] between experimental group and control group were significantly different （all P〈0.05）. Conclusion β-catenin can play a protective role for injuried cells caused by liver ischemia-reperfusion through anti-apoptosis and anti-inflammation.